Selecting anonymous users based on user location history

Abstract

Provided is a process that includes: obtaining, at a survey-participant identification system, location histories from client devices, and the location histories indicating locations of the client device over time; associating each of the location histories with an anonymous pseudonym of the survey candidate; storing the location histories and the association with the anonymous pseudonyms in memory accessible to the server; obtaining, at the survey-participant identification system, criteria by which to select survey candidates, the criteria specifying locations relevant to a survey; selecting, with the survey-participant identification system, anonymous pseudonyms in memory that are associated with a location history that satisfies the criteria; and sending messages to the client devices inviting survey candidates corresponding to the selected anonymous pseudonyms to further identify themselves to participate in the survey.

What is claimed is: 
     
         1 . A tangible, non-transitory, machine-readable medium storing instructions, that when executed, cause one or more processors to perform operations comprising:
 obtaining, with a computer system, a first set of obfuscated values formed by:
 obtaining locations of a mobile computing device a plurality of times over a duration of time to obtain a location history of time-stamped geolocations of the mobile computing device spanning a plurality of days; 
 determining, with one or more processors of the mobile computing device, reduced resolution versions of the time-stamped geolocations in the location history; and 
 determining, with the one or more processors of the mobile computing device, a first set of obfuscated values based on the reduced resolution versions of the time-stamped geolocations; 
   after obtaining the location history of time-stamped geolocations of the mobile computing device spanning the plurality of days, receiving, at the computer system, from another computing device, a query having location as a criterion;   in response to receiving the query, accessing, with the computer system, the first set of obfuscated values;   determining, with computer system, that the location history satisfies the criterion without de-obfuscating the first set of obfuscated values and without the location history being accessible via inspection of the computer system; and   storing a result of the determination in memory of the computer system.   
     
     
         2 . The medium of  claim 1 , wherein:
 determining the first set of obfuscated values comprises determining a first hash value based on at least at least some of the reduced resolution versions of the time-stamped geolocations; and   determining that the location history satisfies the criterion comprises determining a second hash value based on the criterion and determining that the second hash value matching the first hash value.   
     
     
         3 . The medium of  claim 1 , wherein:
 determining the first set of obfuscated values comprises determining different respective cryptographic hash values each corresponding to different respective ones of the reduced resolution versions of the time-stamped geolocations.   
     
     
         4 . The medium of  claim 1 , wherein:
 determining the reduced resolution versions of the time-stamped geolocations in the location history comprises determining reduced resolution versions of both geolocations and time-stamps in the location history.   
     
     
         5 . The medium of  claim 4 , wherein:
 determining the first set of obfuscated values comprises determining a given one of the first set of obfuscated values based on both a given one of the reduced resolution version of geolocation and a corresponding given one of the reduced resolution versions of time stamps.   
     
     
         6 . The medium of  claim 1 , wherein:
 determining the first set of obfuscated values comprises determining an encrypted value based on at least at least some of the reduced resolution versions of the time-stamped geolocations; and   determining that the location history satisfies the criterion comprises determining that the location history satisfies the criterion without decrypting the encrypted value.   
     
     
         7 . The medium of  claim 1 , wherein:
 the reduced resolution versions of the time-stamped geolocations in the location history are encoded in relative terms, with reference to location relative to another entity.   
     
     
         8 . The medium of  claim 7 , wherein the other entity is a landmark. 
     
     
         9 . The medium of  claim 1 , wherein the computer system is remote from the mobile computing device. 
     
     
         10 . The medium of  claim 9 , wherein the computer system includes the mobile device and a remote server system and the location history is not provided to the remote server system. 
     
     
         11 . The medium of  claim 1 , wherein the computer system is the mobile computing device. 
     
     
         12 . The medium of  claim 1 , wherein the query includes location criteria that specify a plurality of different locations, the criteria including the criterion. 
     
     
         13 . The medium of  claim 12 , wherein:
 the criteria specify alternative locations and alternative times; and   determining that the location history satisfies the criterion comprises:
 expanding the alternative locations and alternative times into a set of permutations of combinations of locations and time; 
 determining, for each member of the set, whether the the location history corresponds to the respective member of the set. 
   
     
     
         14 . The medium of  claim 1 , wherein the mobile computing device is caused to obtain the query via a push communication to the mobile computing device. 
     
     
         15 . The medium of  claim 1 , wherein the operations comprise:
 executing an anonymous-location tracker.   
     
     
         16 . The medium of  claim 1 , wherein the operations comprise:
 executing an anonymous account creator; and   executing an anonymous-data intake module.   
     
     
         17 . The medium of  claim 1 , wherein the operations comprise:
 steps for selecting survey participants based on the location history of those participants while preserving the participant's privacy.   
     
     
         18 . The medium of  claim 1 , wherein the operations comprise:
 causing the mobile computing device to present an offer to a user of the mobile computing device in response to determining that the location history satisfies the criterion.   
     
     
         19 . The medium of  claim 1 , wherein the operations further comprise:
 causing the mobile computing device to present an invitation to participate in a survey in response to determining that the location history satisfies the criterion.   
     
     
         20 . A method comprising:
 obtaining, with a computer system, a first set of obfuscated values formed by:
 obtaining locations of a mobile computing device a plurality of times over a duration of time to obtain a location history of time-stamped geolocations of the mobile computing device spanning a plurality of days; 
 determining, with one or more processors of the mobile computing device, reduced resolution versions of the time-stamped geolocations in the location history; and 
 determining, with the one or more processors of the mobile computing device, a first set of obfuscated values based on the reduced resolution versions of the time-stamped geolocations; 
   after obtaining the location history of time-stamped geolocations of the mobile computing device spanning the plurality of days, receiving, at the computer system, from another computing device, a query having location as a criterion;   in response to receiving the query, accessing, with the computer system, the first set of obfuscated values;   determining, with computer system, that the location history satisfies the criterion without de-obfuscating the first set of obfuscated values and without the location history being accessible via inspection of the computer system; and   storing a result of the determination in memory of the computer system.